Coupling for sander drum shafts



July 5, 1932.

C. H. PETSKEYES COUPLING FOR SANDER DRUM SHAFTS Filed May 28, 1930 I; zix lw INVEENTOR.

C las l-IPafrslCeBQs fi A TTORNE Y.

Patented July 5, I932 CHARLES H. PETSKEYES, or. CINCINNATI. 01110,AssI'eNoIt 'r'o TIIEJ. AQJIAY &

COMPANY, or CINCINNATI, 310, s. CoRroRn'rIoNor WEST VIRG NIA COUPLINGFOR SANDER. DRUMt srrnr'rs Application filed May-2s,

This invention relates to an improved coupling for sander drumshafts ofthe, type having a combined rotaryand reciprocating motion. 1. Theprincipal object of theinvention is to provide, in such a coupling, acircular row ofalls (or rollers) disposed between theteeth Other objectsand advantages of the invention will become apparent upon a fullunderstanding of the construction, arrangement and operation of thecoupling.

My invention consists in the construction,

combination, location and arrangement ofparts as set forth and claimed.7

In the drawing:

Fig. 1 is a sectional view through the coupling end of the motorhousing, parts appearing in elevation;

Fig. 2 is an end elevation of the motor shaft coupling member; 7

Fig. 3 is an end elevation of the sander drum shaft coupling member; andV Fig. 4 is an isometric view of the couplin members showing some of theballs interposed therebetween.

In the embodiment of my invention as illustrated and which shows apreferred construction I provide an improved coupling for sander drumshafts comprising coupling members 1 and 2 and balls 3. Coupling member1 iskeyed or otherwise fixed for rotation with motor shaft 4 of motor 5and is retained upon said shaft as by retaining collar 6' and bolt 7 orother suitable or equivalent means. likewise keyed or fixed for rotationwith sander drum shaft 8 andis retained upon said shaft by retainer 9and bolt 10'or other suitable means, as clearly shown in Fig. 1.

Coupling member 1 is rotatably supported within motor housing ll'by ballbearings 12, the inner race 13 of which is locked between said couplingmember 1 and spac- Coupling member 2 is 3 are held between the teethorjaws 11a and ?2a of coupling members 1 and2, respective- 'ly. Withreciprocating coupling member. 2" thusrotatedby coupling member 1through i ;the balls .3 "the sander -drum; shaft v8 will be rotated withsaid member 2'as, it isjfixe'd.

1 30. Serial No 456,528.

ing member 1 1 by collar 6, bolt-.7 and shoulder 15 the latter beingformedupon the mo-. tor shaft 4. The outerrace '16 of bearing 12 is heldagainst annular shoulder 17 (formed within motor housing .11) by spacer1 8 and said spacer is held against said outer race 16 by the end cover19 of motor housing ,11.

This Cover 19 is removablyfattachedjto mo- 1 tor housing lliby bolts 20,and is provided with a. centralbore 21 toreceive the sander drum shaft8. l

1 End ofsandendruinshaft s is slightly reducediindiameter to. provideshoulder 86 and is rotatably mounted-upon the balls 22 within the motorhousingll. These balls 22, as shown in Fig. 1, are mounte'd between in-,nor ball race 23 and intermediate ball race 24;, the latter race beingsoicut as to make the *balls 22 self-aligning.- As 1 sanderv drum shaft8 is reciprocated, while it is being rotated (as iswell-known to thoseskilled in the, art of endless bed drum sanders) the balls .25 areprovided to carry said recipror eating motion of the drum shaft. Thesander drum shaft bearin'g forms no part of. the present invention butis described briefly for the purpose of 'givingia better-under standingof the improved icouplingf Balls 25 :are. received betweenintermediategball race 24 and outer ball race 26 and are heldvtherebetween by retaining member 27. The

outer ballrace 26is held between shoulders 18a and 19a offspacer 18 andcover 19, re;

spectively.f b V g In operation the coupling functionsin the followingmanner: 5

shaft 4 is revolved 'and as the coupling mem- When motor-L5 is .set intomotion, motor 'ber 1 is fixed thereto it likewise is revolvedwithin-ball bearings 12, carried by housing 11 as previously described.This rotarynotion 'of the coupling 'member 1 is imparted toreciprocating couplingmember 2 through the ballsf3. 'As best shown inFig. 4, the balls thereto, as'before described. The mechanism forreciprocating the sander drum shaft 8 is not shown, but it operates inuni-v son with the rotation of motor shaft 4: so

that coupling vmember 2 is moved towards and from coupling member 1whi1esaidcouplings are rotating. together by means of'the balls 3. Thusitwillbe seen that the balls 3 serve a double purpose, i. -e.-they actas a driver between theteeth 1a and-2a of coupling members 1 and 2,respectively, and

serve as a bearing to accommodate-the lon-fgitudinal reciprocatingmotion of teeth 2a and thus reduce frictionbetween-ithe con-f plingmembers to a minimum. V

My construction of coupling permits the shafts to be tilted atdifi'erentangles relative to eachother without any binding effect be? tween thecooperating parts of the coupling; One feature of my inventio'n' is thatcentrif ugal force urges the balls outwardly when the-coupling is inmotion, thereby locking the ballsbetween their res-pective'jaws orteeth; second, theballs being locked, because of the above,automatically ho'ldcthe' drum tight with the' driving 'means,eliminating all backlash or lost motion because of-wear;

third, it permits ofusing one set or row of saidItee'tli being aced,apart Land hawng a circular row of anti-friction driving balls mounted;betweenthe respective teeth of the cooperating coupling members, wherebyas said coupling isirotated centrifugal force will tendto spreadtheballs outwardly from diameter and against the curved portion of onetooth and the" straight portion of the cooperating tooth, thu's lockingthe teeth "together and eliminating any backlash' or lost motion whilein-operation and permitting-reteeth. I oni enns PETSVKEYES.

balls, and dueto itsconstruction we are able to:ali,n or adjust out 'ofalignment the two connectingshafts and still maintain the pre-', 1

determined efiicien'cy; While I have shown and'described one ,form ofthe invention 'for thepurpose "of 'exemplification, it isto beunderstood that i i i the invention is also susceptible of embodimentinother modified form's comingequajlly "within the scope of the appendedclaim s,-as,

for example, rollers, or yother means, can be substituted in place' oftheballsS.

What 'Icla im 'asnew and desire to seeuf by Letters Patent is: A 1

g A coupling for sander drum shafts com prising, incombinatlonfa couphngmember mounted for rotary motion, means for rotat- "mg said-member,drlvingteeth on each mem- "her,1the driving teethon onemembe'rbeingun-'derc'u't with the surface adjacent to the' pe-' riphery curved andthe-remaining portion 7 straight fand the teeth of the other memberbeing undercut with the portion, adjacent to I the periphery straightand the remaining 1 portion.curved, said teeth being spaced apart I :andhaving; a circ ular row of anti-friction v i I driving balls mountedwithin. said undercut portion-between .therespective teeth of the p g Vcooperating coupling members, whereby said coupling is rotatedcentrifugal force "willntend to spreadthe balls outwardly fromtheacenter and'aga'inst the curved portion of one tooth andfthe'straightportion of the co-' I "Operating 'tooth, thus locking the teeth toiigether andeliminating-anybacklash or lost "K motion whilein perationanderinitting recipr'ocatingmotion "ofthe ball between said

